Conventional video conferencing systems include a number of endpoints communicating real time multimedia such as video, audio, and data streams. In a conventional video conferencing session, the endpoints transmit multimedia streams directly point to point or through a central unit in a multipoint network. The video conferencing session is established by connecting at least two endpoints to a central unit using a call control protocol that negotiates video formats and connection information for sending and receiving multimedia streams. In conventional video conferencing systems, communication between endpoints is either enabled or disabled.